Towards new mycobacterial vaccines.

BCG, the Bacillus of Calmette and Guérin, has been used as a vector for the presentation of foreign antigens. The nef gene of HIV was cloned and expressed in BCG. A specific cellular immune response against Nef was observed following inoculation of mice. As a model system beta-galactosidase has also been expressed in BCG. Antibody responses against beta-galactosidase in addition to cellular responses were observed. Mucosal immunity was demonstrated after oral immunization of mice. With the aim of isolating new vaccines against tuberculosis, transposon mutagenesis was investigated. By using Tn610, representative libraries of Mycobacterium smegmatis insertion mutants were constructed.